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1.
抑前胸腺肽在家蚕体内的活性作用   总被引:1,自引:0,他引:1  
家蚕Bombyx mori抑前胸腺肽是昆虫脑神经肽的一种,体外实验表明它能抑制处于活动时期的家蚕前胸腺合成蜕皮激素,因此抑前胸腺肽可能对昆虫的变态起着重要的作用。将抑前胸腺肽以不同的浓度分单一注射和加强注射导入家蚕体内,不同的时间间隔取样,利用蜕皮激素放射免疫分析方法,观察到了抑前胸腺肽在家蚕体内的活性作用以及引起家蚕体内血淋巴中蜕皮激素浓度的动态变化,首次证明了抑前胸腺肽在体内对家蚕前胸腺合成蜕皮激素有强烈的抑制作用。  相似文献   

2.
刘新  田中良明 《昆虫学报》2002,45(3):301-306
家蚕Bombyx mori抑前胸腺肽是昆虫脑神经肽的一种,体外实验表明它能抑制处于活动时期的家蚕前胸腺合成蜕皮激素,因此抑前胸腺肽可能对昆虫的变态起着重要的作用。将抑前胸腺肽以不同的浓度分单一注射和加强注射导入家蚕体内,不同的时间间隔取样,利用蜕皮激素放射免疫分析方法,观察到了抑前胸腺肽在家蚕体内的活性作用以及引起家蚕体内血淋巴中蜕皮激素浓度的动态变化,首次证明了抑前胸腺肽在体内对家蚕前胸腺合成蜕皮激素有强烈的抑制作用。  相似文献   

3.
通过解剖镜和扫描电子显微镜对意大利工蜂Apismellifera ligusticaL.前胃的形态结构进行了观察,发现前胃包括前胃瓣和前胃管两部分。前胃瓣是由4个瓣片环围而成,球形,在蜜囊中,每个瓣片的长度约为0.8mm,前端为三角形结构,可以运动,边长约为0.35mm,三角形的前缘有较长的毛形结构。在每个三角形顶端各有一个直径约为50μm瘤形突起。前胃瓣最大孔径为0.89~1.00mm,具有调整和控制食物进入中肠的功能。前胃管是一直径0.01~0.02mm的较为柔软的管道,插入中肠5mm,该结构可防止中肠食物的倒流。前胃瓣上有7种毛状结构,分布在前胃瓣的不同部位,该结构的功能是分离和过滤、捕捉和感觉功能。本研究为理解工蜂前胃在消化系统中的功能和作用以及昆虫形态学和昆虫分类学提供理论依据。  相似文献   

4.
蚂蚁亲系识别及研究方法进展   总被引:9,自引:2,他引:7  
谭声江  刘志斌 《昆虫知识》1998,35(4):246-249
1前言亲系识别(Kinrecognition)是指社会性昆虫具有识别亲属与非亲属的能力,它被认为是昆虫社会性起源和演化的必要条件。此外,亲系识别在昆虫个体间的通讯、协作和繁衍等社会生活中具有重要作用。蚂蚁是社会性昆虫,许多种类表现出社群封闭性,即社群内相互合作和利它,而社群间表现出相互排斥,甚至强烈的进攻性。这一现象表明蚂蚁具有识别亲系的能力。揭示亲系识别的化学本质和遗传根源,不仅有助于对昆虫超社会性的起源和演化的研究,而且对行为学的其它相关学科(如行为生态学、行为遗传学、行为生理学),进化生物学的研究以及人…  相似文献   

5.
昆虫蛹滞育的神经内分泌调控   总被引:2,自引:0,他引:2  
从神经内分泌的角度,分别介绍了脑、前胸腺和咽侧体在昆虫蛹滞育中所起的作用。脑主要是通过对促前胸腺激素的合成和释放的控制来参与滞育调节的;而前胸腺的活性过低,分泌的蜕皮激素远远低于启动成虫发育所需要的量,是导致蛹滞育的最根本原因;咽侧体在某些虫种中对蛹滞育可能起到间接的调控作用。  相似文献   

6.
董育新  刘惠霞 《昆虫知识》1998,35(4):249-251
胰蛋白酶是脊椎动物消化道中一种主要的蛋白水解酶,由胰脏产生。以无活性的前体──酶原形式释放,一经进人肠腔,由肠激酶活化自其N端水解掉一段6肽(活化肽)而生成有活性的胰蛋白酶。它可以有力迅速地激活其它蛋白酶原(糜蛋白酶原、羧肽酶原、弹性蛋白酶原)而行使消化功能[1]。昆虫胰蛋白酶由中肠肠壁细胞产生分泌进入中肠。过去研究认为:昆虫胰蛋白酶与脊椎动物不同,它不是以无活性的前体释放的,因此就没有相当于脊椎动物的胰蛋白酶原[1]。但最近研究确认,在昆虫消化道中同样存在着类似于脊椎动物的胰蛋白酶原,并对昆虫胰蛋白…  相似文献   

7.
昆虫促前胸腺激素研究进展   总被引:4,自引:0,他引:4  
昆虫促前胸腺激素研究进展李毅平龚和(中国科学院动物研究所,北京100080)关键词促前胸腺激素受体信号系统促前胸腺激素(prothoracicotropichor-monePTTH)因其促进前胸腺(PG)合成和分泌蜕皮激素而得名,以前也称为脑激素,因...  相似文献   

8.
昆虫标本馆建设与昆虫系统学的未来   总被引:6,自引:0,他引:6  
昆虫标本馆是昆虫标本的保藏、研究和科学教育的实体,代表国家或者区域水平,致力于研究昆虫多样性、揭示昆虫进化规律,为国民经济建设持续发展服务。昆虫系统学研究是昆虫标本馆研究人员的主要任务,它的发展与昆虫标本馆的建设唇齿相依。本文阐述了昆虫标本馆的功能与作用,建设昆虫标本馆的重要性和迫切性;展望了昆虫系统学的未来以及昆虫系统学发展的机遇。  相似文献   

9.
记述了采自湖北省的蚁科昆虫2新种,即九宫山凹头臭蚁Phildris jiugongshanensis sp.nov.和七齿前结蚁Prenolepis septemdenta sp.nov.。文中提供了凹头臭蚁属Philidris Shattuck和前结蚁属Prenlepis Mayr在我国所有种的检索表。新种模式标本保存于湖北民族学院昆虫标本室。  相似文献   

10.
崔建新  彩万志 《昆虫知识》2007,44(1):138-142
鞘翅型蝽类昆虫前翅发达,与甲虫的前翅相似。类群涉及鞭蝽型、蝎蝽型、细蝽型、臭虫型、蝽型中的栉蝽科、裂蝽科、小潜蝽科、固蝽科、蚤蝽科、涯蝽科、网蝽科、盲蝽科、长蝽科、缘蝽科共10个科。它们的生境多样,包括水底小石块下面、水生植物上、海岸潮间区石隙中、蚂蚁巢穴中、沙漠灌木植物上、土中、沙砾中、枯枝落叶层和苔藓上,这些生境的共同点是其对前翅的保护功能的选择压力明显大于对前翅飞行功能的选择压力。此类昆虫的前翅特化的类型分为两类,一类膜区完全退化或极度退化,由革区和爪区(愈合或不愈合)构成鞘质前翅的主体;另一类膜区发达,占鞘质前翅的主体;大部分前翅鞘质化的蝽类属于第一种类型;仅个别长蝽科的昆虫属于第二类,如巨膜长蝽Jakowleffiasetulosa(Jakowleff)。  相似文献   

11.
12.
The present paper is part of taxonomic study on Chinese Phyllanthoideae. Included in it are two new varieties, Leptopus esquirolii var. villosus and Drypetes hainanensis var. longistipitata, one new combination, Glochidion triandrum var. siamense, and seven new records in China: Drypetes salicifolia, D. hoaensis. Actephila subsessilis, Glochidion khasicum, G. nubigennum, Bridelia spiosa and B. poilanei. In addition, seventeen taxon names are newly reduced: Liodendron formosanum = Drypetes formosana, Liodendron matsumurae = Drypetes matsumurae, D. longipes = D. indica, Antidesma paxii = A. acidum, A. hiiranense, A. filipes and A. pentandrum var. hiiranense = A. japonicum, A. calvescens = A. montanum, A. microphyllum = A. venosum, Breynia stipitata var. formosana and B. jormosana = B. vitis-idaea, Glochidion zeylanicum var. tomentosum = G. hirsutum, G. rubidulum = G. thomsonii, G. acuminatum = G. triandrum, G. fagifolium and Phyllanthus fagifolius = Glochidion sphaerogynum, Bridelia penangiena = B. insulana, B. henryana = B. tomentosa. All the types are kept in SCBl and PE.  相似文献   

13.
At one spectrum extreme, Astrobiology conjectures that for exoplanets with Goldilocks conditions, terrestrial-like life is inevitable. Moreover, it is envisaged that via panspermia, terrestrial-like life and its precursors are transferred among galaxies, stars, and within solar systems via transiting comets, asteroids, and planetoids. In addition, expelled stars, which have solar systems, it is inferred, transfer life as well. However, at the other extreme, we propose a paradigm shift that on some planets, subject to non- Goldilocks conditions, metal machine life could arise, ab initio, and evolve viruses, intelligence, and civilizations, conjointly. Accordingly, intelligent mechanized civilizations could readily and efficiently commence space exploration. Furthermore, as a counter paradigm shift, such civilizations could experiment and produce non-metallic life, based on carbon and other non-metal elements, under suitable conditions, related to Goldilocks life. Even a single example of validated interstellar or intergalactic communication received on the Earth would support the existence of life elsewhere. However, the communication platform should not be restricted to electromagnetic radiation. Other platforms should be included as well - one such example, which would require sophisticated technology, is neutrino communication. This is the case for any advanced civilization, be it metal-machine based, biological-based, and carbon-based. In sum, civilizations based on machine life, would be highly productive due to the longevity and hardiness of machine life. However, significant caveats are raised in this brief report, because possibly dissimilar psychologies and intelligence may lead to conflicts between metal machine life and biological life, inter-paradigm conflict.  相似文献   

14.
The phylogeny of groups within Gobioidei is examined with molecular sequence data. Gobioidei is a speciose, morphologically diverse group of teleost fishes, most of which are small, benthic, and marine. Efforts to hypothesize relationships among the gobioid groups have been hampered by the prevalence of reductive evolution among goby species; such reduction can make identification of informative morphological characters particularly difficult. Gobies have been variously grouped into two to nine families, several with included subfamilies, but most existing taxonomies are not phylogenetic and few cladistic hypotheses of relationships among goby groups have been advanced. In this study, representatives of eight of the nine gobioid familes (Eleotridae, Odontobutidae, Xenisthmidae, Gobiidae, Kraemeriidae, Schindleriidae, Microdesmidae, and Ptereleotridae), selected to sample broadly from the range of goby diversity, were examined. Complete sequence from the mitochondrial ND1, ND2, and COI genes (3573 bp) was used in a cladistic parsimony analysis to hypothesize relationships among the gobioid groups. A single most parsimonious topology was obtained, with decay indices indicating strong support for most nodes. Major phylogenetic conclusions include that Xenisthmidae is part of Eleotridae, and Eleotridae is paraphyletic with respect to a clade composed of Gobiidae, Microdesmidae, Ptereleotridae, Kraemeriidae, and Schindleriidae. Within this five-family clade, two clades are recovered. One includes Gobionellinae, which is paraphyletic with respect to Kraemeriidae, Sicydiinae, Oxudercinae, and Amblyopinae. The other contains Gobiinae, also paraphyletic, and including Microdesmidae, Ptereleotridae, and Schindleriidae. Previous morphological evidence for goby groupings is discussed; the phylogenetic hypothesis indicates that the morphological reduction observed in many goby species has been derived several times independently.  相似文献   

15.
1. Acetylcholine receptors were initially defined as nicotinic or muscarinic, based on selective activation by two natural products, nicotine and muscarine. Several further nicotinic agonists have been discovered from natural sources, including cytisine, anatoxin, ferruginine, anabaseine, epibatidine, and epiquinamide. These have provided lead structures for the design of a wide range of synthetic agents.2. Natural sources have also provided competitive nicotinic antagonists, such as the Erythrina alkaloids, the tubocurarines, and methyllycaconitine. Noncompetitive antagonists, such as the histrionicotoxins, various izidines, decahydroquinolines, spiropyrrolizidine oximes, pseudophrynamines, ibogaine, strychnine, cocaine, and sparteine have come from natural sources. Finally, galanthamine, codeine, and ivermectin represent positive modulators of nicotinic function, derived from natural sources.3. Clearly, research on acetylcholine receptors and functions has been dependent on key natural products and the synthetic agents that they inspired.  相似文献   

16.
The phylogenetic relationships of the caryophyllidia-bearing dorids are studied, based on the examination of the type species of all the genera previously described. The phylogenetic hypothesis supports that the caryophyllidia-bearing dorids are a monophyletic group and the sister group of the clade formed by Astemnotus Ehrenberg, 1831 and Halgerda Bergh, 1880. Several genera previously considered as valid or regarded as uncertain are here synonymized: Peronodoris Bergh, 1904, Trippa Bergh, 1877, Phlegmodoris Bergh, 1878, Petelodoris Bergh, 1881, Kentrodoris Bergh, 1876, Audura Bergh, 1878, Centrodoris P. Fischer, 1883, Anisodoris Bergh, 1898, Awuka Er. Marcus, 1955, Rhabdochiia P. Fischer, 1883, Boreodoris Odhner, 1939, Dictyodoris Bergh, 1880, Gravieria Vayssiere, 1912, Aporodoris Ihering, 1886. The following genera are regarded as valid: Astemnotus, Atagema J.E. Gray, 1850, Jorunna Bergh, 1876, Platydoris Bergh, 1877, Diaulula Bergh, 1878, Rostanga Bergh, 1879, Halgerda Bergh, 1880, Baptodoris Bergh, 1884, Gargamella Bergh, 1894, Alloiodoris Bergh, 1904, Sclerodoris Eliot, 1904, Taringa Er. Marcus, 1955, Thorybopus Bouchet, 1977. The new genus Nophodoris is described based on two new species from New Caledonia deep waters. Two additional new species from New Caledonia belonging to the genera Atagema and Gargamella are also described. Nomenclatural and taxonomic problems are discussed, and several type species, neotypes and lectotypes are selected.  相似文献   

17.
The species of the genus Trichoteleia Kieffer (Hymenoptera: Platygastridae) are revised: 42 species are recognized, of which two were previously named and are redescribed: Trichoteleia afo Talamas, sp. n., Trichoteleia albidipes Kieffer, Trichoteleia bicolor Talamas, sp. n.; Trichoteleia bidentata Talamas sp. n.; Trichoteleia carinata Talamas, sp. n.; Trichoteleia cincta Talamas & Masner, sp. n.; Trichoteleia delilah Talamas, sp. n.; Trichoteleia eburata Talamas, sp. n.; Trichoteleia echinata Talamas, sp. n.; Trichoteleia fisheri Talamas & Masner, sp. n.; Trichoteleia funesta Talamas, sp. n.; Trichoteleia halterata Talamas & Masner, sp. n.; Trichoteleia hemlyae Talamas & Masner, sp. n.; Trichoteleia irwini Talamas & Masner, sp. n.; Trichoteleia janus Talamas, sp. n.; Trichoteleia jiro Talamas, sp. n.; T. ketrona Talamas, sp. n.; Trichoteleia levii Talamas & Johnson, sp. n.; Trichoteleia longiventris Talamas & Masner, sp. n.; Trichoteleia minima Talamas, sp. n.; Trichoteleia nify Talamas & Masner, sp. n.; Trichoteleia oculea Talamas, sp. n.; Trichoteleia orona Talamas & Masner, sp. n.; Trichoteleia parvipennis Talamas & Masner, sp. n.; Trichoteleia pauliani (Risbec); Trichoteleia picturata Talamas, sp. n.; Trichoteleia prima Talamas, sp. n.; Trichoteleia prolixa Talamas, sp. n.; Trichoteleia quazii Talamas, sp. n.; Trichoteleia ravaka Talamas, sp. n.; Trichoteleia rugifrons Talamas & Masner, sp. n.; Trichoteleia solocis Talamas, sp. n.; Trichoteleia sphaerica Talamas, sp. n.; Trichoteleia subtilis Talamas & Masner, sp. n.; Trichoteleia tahotra Talamas & Masner, sp. n.; Trichoteleia takariva Talamas, sp. n.; Trichoteleia tezitra Talamas, sp. n.; Trichoteleia tigris Talamas, sp. n.; Trichoteleia tonsa Talamas, sp. n.; Trichoteleia warreni Talamas & Masner, sp. n.; Trichoteleia xantrox Talamas, sp. n.; Trichoteleia zuparkoi Talamas & Masner, sp. n. A neotype is designated for Trichoteleia albidipes and a lectotype is designated for Trichoteleia pauliani.  相似文献   

18.
This study describes a method for predicting and classifying oxygen-binding pro- teins. Firstly, support vector machine (SVM) modules were developed using amino acid composition and dipeptide composition for predicting oxygen-binding pro- teins, and achieved maximum accuracy of 85.5% and 87.8%, respectively. Sec- ondly, an SVM module was developed based on amino acid composition, classify- ing the predicted oxygen-binding proteins into six classes with accuracy of 95.8%, 97.5%, 97.5%, 96.9%, 99.4%, and 96.0% for erythrocruorin, hemerythrin, hemo- cyanin, hemoglobin, leghemoglobin, and myoglobin proteins, respectively. Finally, an SVM module was developed using dipeptide composition for classifying the oxygen-binding proteins, and achieved maximum accuracy of 96.1%, 98.7%, 98.7%, 85.6%, 99.6%, and 93.3% for the above six classes, respectively. All modules were trained and tested by five-fold cross validation. Based on the above approach, a web server Oxypred was developed for predicting and classifying oxygen-binding proteins(available from http://www.imtech.res.in/raghava/oxypred/).  相似文献   

19.
Mating systems are reported for taxa of polypores and agarics considered related. Taxa areDictyopanus pusillus, Favolus alveolaris, F. tenuiculus, Lentinus bertierii, L. crinitis, L. punctaticeps, L. strigellus, L. strigosus, L. suavissimus, Pleurotus australis, P. levis, P. tuberregium, Polyporus ciliatus, P. elegans, P. squamosus, andP. varius. All are tetrapolar exceptP. elegans.  相似文献   

20.
In this paper, one new species, four new varieties and thirteen new records of Characeae from Hunan, China, are reported. They are Chara quadriscutulum, sp. nov., Nitella axilliformis var. biformis, var. nov., N. microcarpa var. unicarpa, var. nov., Chara braunii var. cylindrospora, var. nov., C. hydropitys var. hunanensis, var. nov., Nitella microcarpa Braun, N. leptoclada Braun, N. annandalei Pal, N. confervacea A. Braun, N. gracilliformis J. Groves, N. inversa Imahori, N. musashiensis Morioka, N. paucicostata T. F. Allen, N. acuminata var. gollmeriana (A. Br.) Zanev. et Wood, Tolypella boldii Sawa. Chara longifolia Robinson, C. pistianensis J. Vilhelm, C. grovesii Pal.  相似文献   

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